<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<style>
    .box-short {
        height: 200px;
        width: 200px;
        background-color: red;

    }
    .box-big {
        height: 400px;
        width: 400px;
        background-color: green;
    }
</style>
<body>
    
    <div class="box-short"></div>
    <div class="box-big"></div>
</body>
</html>